B. Spilsbury defines a bruise
as a hurt or injury to the body by a blunt or heavy instrument causing
discoloration, but no laceration of the skin. Bruises consist of
blood escaping from ruptured capillaries and small veins spreading
into the surrounding tissue.

In forensic it can be very important
to age bruises. For example in a case of child abuse.

It's very difficult to age a
bruise. The only indicator of time is the color of the injury.
Now the big question is, at what time the color is changing, and
which color is the significant one.

There are some authors that
put up a table on the time sequence of color changes in bruises:

Camps:

red

immediate

dusky purple / black

soon after

green

days 4 -5

Yellow

days 7 - 10

resolution

days 14 - 15

Glaister:

violet

immediate

blue

day 3

green

days 5 - 7

yellow

days 8 - 10

resolution

days 13 - 18

Polson and Gee:

red dark / red black

< 24 h

greenish tinge

around day 7

yellow

around day 14

resolution

up to 30 days

Smith and Fiddes:

red

immediate

purple black

soon after

green

days 4 -5

yellow

days 7 - 10

resolution

days 14 - 15

N.E.I Langlois and G.A. Gresham:

found out that the only significant color is yellow. They
did a study in which 369 Photographs were taken. The results
of this study is that the earliest time where the yellow color
is appearing, is 18 hours after the impact. Any other color
could be found before and after this time. This means that if
there is yellow on a bruise it is older than 18 hours. This
18 hours "cut off" the yellow can appear are much earlier than
the tables above shows.

A recent paper
of Paliwal and Basant Lal shows that the healing of a bruise can
take much more than the usual described 13 to 15 days.

Therefore decided to do an example on myself. I went
into Charly Bühlers Boxing club and told him to give me the most
brute boxer. After a few seconds I was standing in the ring with
the three time Algerian championship winning boxer...... well maybe
this example was a little involuntary.